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United States Patent | 6,243,674 |
Yu | June 5, 2001 |
A sound compression system adaptively switches codebooks in and out based on a calculation carried out with the output of the codebook. The system uses three separate codebooks: adaptive vector quantization codebook, real pitch codebook, and noise codebook. The perceptually-weighted filter is generated adaptively using the predictive coefficients from the current sub-frame.
Inventors: | Yu; Alfred (Irvine, CA) |
Assignee: | American Online, Inc. (Dulles, VA) |
Appl. No.: | 033223 |
Filed: | March 2, 1998 |
Current U.S. Class: | 704/221; 704/233; 704/242; 704/244; 704/245 |
Intern'l Class: | G10L 019/12 |
Field of Search: | 704/205,210,216,233,230,222,207,214,242,244,245,249,236,221 |
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